The designer behind the latest colorway for Coco Gauff's signature New Balance shoe, the Coco CG1, is one who's close to home for the American teenager. In fact, he lives in her house. 

Gauff announced the launch of her signature shoe last year, and now, the first-ever New Balance kids performance tennis shoe, the Coco CG1 Kids, has been designed by her 9-year-old brother, Cameron Gauff. 

The shoe, which comes in a vibrant blue, green and orange colorway, is on sale now, and is the embodiment of both creative expression for Gauff's youngest sibling, and the bond that he shares with his big sister.

"For every Christmas, he would ask for something art related," she told People magazine in a recent interview. "Now, on my door in my room, I have one of his drawings up there."

New Balance helped facilitate Cameron Gauff's debut design when product designers gave him a 'how to make a sneaker' book, complete with coloring pages. He later sent a collection of drawings to the sneaker company, in a variety of colorways, and New Balance went on to work the concept into a new shoe.

"He was really excited," Gauff said. "I think he kind of sensed [what would happen] in a way because they asked him to draw on this shoe and then for the paper, so he's young, but he kind of put two and two together."

As far as the youngster's inspiration for the design? His sister says it was all about the vibes. 

"I asked him about that and he said it was, 'Just what I was feeling,'" she said. "I think that's just like what's fun about being a kid in general. As you get older, you tend to overthink things. But I feel like kids really trust their first instinct and that's kind of what he did. He just said he just thought the colors look cool together."

Will Gauff debut a grown-up version of her brother's design this month during the Sunshine Double? Only time will tell. As for Cameron? He "wears the shoes all the time," she says. 

"[He] probably brags about it to his classmates," she joked.